Abstract: A terahertz wave lens includes a substrate having a surface provided with an uneven structure that changes a phase of the terahertz wave. The uneven structure includes a plurality of holes that are periodically arranged. The uneven structure includes a plurality of regions where the plurality of holes are arranged. A height of the hole in a thickness direction of the substrate and a width of the pillar differ for each of the regions. Outer end portions of the uneven structure in the thickness direction are located on the same plane.

Abstract: Structures operable to detect radiation are described. The structure may two screens with a phosphor layer, respective. The structure may further include a photosensor array disposed between the first screen and the second screen such that the photosensor array directly contacts the first screen or is directly attached to the first screen using an optical adhesive and directly contacts the second screen or is directly attached to the second screen using an optical adhesive.

Abstract: A photoelectric conversion element uses organic materials and is provided with improved quantum efficiency and response rate. The organic photoelectric conversion element includes, in a photoelectric conversion layer, p-type molecules represented by Formula (1): in which A represents any one of oxygen, sulfur or selenium, any one of R1 to R4 represents a substituted or unsubstituted aryl or heteroaryl having 4 to 30 carbon atoms, the remainder of R1 to R4 each represent hydrogen, any one of R5 to R8 represents a substituted or unsubstituted aryl or heteroaryl having 4 to 30 carbon atoms, and the remainder of R5 to R8 each represent hydrogen.

Abstract: Embodiments of the disclosure provide an apparatus for emitting laser light and a system and method for detecting laser light returned from an object. The system includes a transmitter and a receiver. The transmitter includes one or more laser sources, at least one of the laser sources configured to provide a respective native laser beam having a wavelength above 1,100 nm. The transmitter also includes a wavelength converter configured to receive the native laser beams provided by the laser sources and convert the native laser beams into a converted laser beam having a wavelength below 1,100 nm. The transmitter further includes a scanner configured to emit the converted laser beam to the object in a first direction. The receiver is configured to detect a returned laser beam having a wavelength below 1,100 nm and returned from the object in a second direction.

Abstract: The semiconductor image sensor device comprises a semiconductor layer having a main surface and an opposite rear surface, and a charge carrier generating component at the main surface. The charge carrier generating component is arranged between a top reflecting layer and a bottom reflecting layer, which are arranged outside the semiconductor layer.

Abstract: A semiconductor light receiving element comprises a light absorption region formed in the vicinity of the main surface of the semiconductor substrate transparent to the incident light; an incident region set to be concentric with and larger than the light absorption region; and a partially spherical concave reflecting portion formed on a back surface of the semiconductor substrate and capable of reflecting incident light incident on the incident region from the main surface side toward the light absorbing region; wherein, when the radius of curvature of the portion is R, the diameter of the incident region is B, the distance between the light absorbing region and the concave reflecting portion is W, and the diameter of the light absorbing region is P, then the radius of curvature R satisfies a condition of 2 BW/(B?P/2)?R?2BW/(B?P).

Abstract: A Group VB element doped with a ?-gallium oxide crystalline material, and a preparation method and application thereof. The series doped with the ?—Ga2O3 crystalline material is monoclinic, the space group is C2/m, the resistivity is in the range of 2.0×10?4 to 1×104?·cm, and/or the carrier concentration is in the range of 5×1012 to 7×1020/cm3. The preparation method comprises steps of: mixing M2O5 and Ga2O3 with a purity of 4N or more at molar ratio of (0.000000001-0.01):(0.999999999-0.99); an then performing crystal growth. The present invention can prepare a high-conductivity ?-Ga2O3 crystalline material with n-type conductivity characteristics by conventional processes, providing a basis for applications thereof to electrically powered electronic devices, optoelectronic devices, photocatalysts or conductive substrates.

Abstract: A cover for an electronic circuit package, including an element having peripheral portions housed in an inner groove of a through opening.

Abstract: An image sensor includes: a photoelectric conversion film that performs photoelectric conversion on light having entered therein; at least two electrodes, including a first electrode and a second electrode, disposed at a surface of the photoelectric conversion film; and at least two electrodes, including a third electrode and a fourth electrode, disposed at another surface of the photoelectric conversion film.

Abstract: Various embodiments of the present application are directed towards an image sensor having a reflector. In some embodiments, the image sensor comprises a substrate, an interlayer dielectric (ILD) structure, an etch stop layer, a wire, and the reflector. The substrate comprises a photodetector. The ILD structure is over the substrate, and the etch stop layer is over the ILD structure. The wire is in the etch stop layer. The reflector is directly over the photodetector and is in the etch stop layer. An upper surface of the wire is elevated above an upper surface of the reflector. By forming the reflector directly over the photodetector, the reflector may reflect radiation that passes through the photodetector without being absorbed back to the photodetector. This gives the photodetector a second chance to absorb the radiation and enhances the quantum efficiency (QE) of the photodetector.

Abstract: An optical waveguide substrate includes a substrate that includes a recess, a buffer layer disposed on a bottom surface and a wall surface of the recess, and an optical waveguide disposed inside the recess with the buffer layer interposed therebetween and having a cladding layer disposed on the buffer layer and a core layer disposed inside the cladding layer.

Abstract: Disclosed is a photodetector which includes, in series along a stacking direction: a first layer forming a substrate of a first semiconductor material; a second layer forming a photoabsorbent layer of a second semiconductor material having a second gap; a third layer forming a barrier layer of a third semiconductor material; and a fourth layer forming a window layer of a fourth semiconductor material, the first material, the third material and the fourth material each having a gap larger than the second gap, the fourth material being n-doped or non-doped and the third material being non-doped or lightly p-doped when the second material is n-doped, and the fourth material being p-doped or non-doped and the third material being non-doped or lightly n-doped when the second material is p-doped.

Abstract: An image sensor with high quantum efficiency is provided. In some embodiments, a semiconductor substrate includes a non-porous semiconductor layer along a front side of the semiconductor substrate. A periodic structure is along a back side of the semiconductor substrate. A high absorption layer lines the periodic structure on the back side of the semiconductor substrate. The high absorption layer is a semiconductor material with an energy bandgap less than that of the non-porous semiconductor layer. A photodetector is in the semiconductor substrate and the high absorption layer. A method for manufacturing the image sensor is also provided.

Abstract: There is described a photodetector for detecting incoming infrared light. The photodetector generally has a substrate; an i-type semiconductor region extending along the substrate, the i-type semiconductor region being sandwiched between a p-type semiconductor region and an n-type semiconductor region; a grating coupler being optically connected to one of two ends of the i-type semiconductor region, the grating coupler redirecting incoming infrared light into and along the i-type semiconductor region via the one of the two ends of the i-type semiconductor region for propagation of infrared light along the i-type semiconductor region; and a photocurrent detection circuit electrically connected to the p-type semiconductor region and to the n-type semiconductor region for detecting a photocurrent resulting from said propagation.

Abstract: Integrated circuits and methods of producing the same are provided. In an exemplary embodiment, an integrated circuit includes a photodetector, where the photodetector includes an impingement photodetector well and a base photodetector well. A transfer transistor overlies the photodetector, where the transfer transistor includes a transfer gate, a source, and a drain. A source contact is electrically connected to the source, and the source contact is also electrically connected to the photodetector.

Abstract: A photosensor device and the method of making the same are provided. In one embodiment, the device includes at least one pixel cell. The at least one pixel cell includes a substrate formed from a semiconductor material, and includes first and second photosensor regions. The first photosensor region is disposed in the substrate and includes a first dopant of a first conductivity type. The second photosensor region is disposed above the first photosensor region and includes a second dopant of a second conductivity type. The second photosensor region can have an increase in dopant concentration from an outer edge to a center portion therein.

Abstract: A photodetector is described along with corresponding materials, systems, and methods. The photodetector comprises an integrated circuit and at least two optically sensitive layers. A first optically sensitive layer is over at least a portion of the integrated circuit, and a second optically sensitive layer is over the first optically sensitive layer. Each optically sensitive layer is interposed between two electrodes. The two electrodes include a respective first electrode and a respective second electrode. The integrated circuit selectively applies a bias to the electrodes and reads signals from the optically sensitive layers. The signal is related to the number of photons received by the respective optically sensitive layer.

Abstract: A photoelectric conversion element includes a buffer layer, a BSF layer, a base layer, a photoelectric conversion layer, an emitter layer, a window layer, a contact layer, and a p-type electrode sequentially on one surface of a substrate, and includes an n-type electrode on the other surface of the substrate. The photoelectric conversion layer has at least one quantum dot layer. The at least one quantum dot layer includes a quantum dot and a barrier layer. A photoelectric conversion member including the buffer layer, the BSF layer, the base layer, the photoelectric conversion layer, the emitter layer, the window layer, and the contact layer has an edge of incidence that receives light in an oblique direction relative to the growth direction of the quantum dot. A concentrator concentrates sunlight and causes the concentrated sunlight to enter the photoelectric conversion member from the edge of incidence.

Abstract: A semiconductor device is disclosed, which includes: at least one device layer being a crystallized layer for example including: a superlattice layer and/or a layer of group III-V semiconductor materials; and a passivation structure comprising one or more layers wherein at least one layer of the passivation structure is a passivation layer grown in-situ in a crystallized form on top of the device layer, and at least one of the one or more layers of the passivation structure includes material having a high density of surface states which forces surface pinning of an equilibrium Fermi level within a certain band gap of the device layer, away from its conduction and valence bands.

Abstract: A light absorption apparatus includes a substrate, a light absorption layer above the substrate on a first selected area, a silicon layer above the light absorption layer, a spacer surrounding at least part of the sidewall of the light absorption layer, an isolation layer surrounding at least part of the spacer, wherein the light absorption apparatus can achieve high bandwidth and low dark current.

Abstract: A light absorption apparatus includes a substrate, a light absorption layer above the substrate on a first selected area, a silicon layer above the light absorption layer, a spacer surrounding at least part of the sidewall of the light absorption layer, an isolation layer surrounding at least part of the spacer, wherein the light absorption apparatus can achieve high bandwidth and low dark current.

Abstract: To provide a solar cell having improved photoelectric conversion efficiency and a solar cell module. A solar cell (10) is provided with a photoelectric conversion portion (20), a light receiving surface electrode (21a) and a back surface electrode (21b). The light receiving surface electrode (21a) is arranged on the light receiving surface (20a) of the photoelectric conversion portion (20). The back surface electrode (21b) is arranged on the back surface (20b) of the photoelectric conversion portion (20). The back surface electrode (21b) includes metal film (21b1) and an electrical connection electrode (21b2). The metal film (21b1) at least partially covers the back surface (20b). The electrical connection electrode (21b2) is arranged on the metal film (21b1).

Abstract: A photodetector structure having a barrier layer disposed between a pair of like-conductively doped semiconductor layers, the barriers layer having a surface area smaller than the surface area of the upper one of the pair of semiconductor layers. A fill material is disposed between outer peripheral edges of the barrier layer and a region between outer peripheral edges of the first and second layers.

Abstract: A small-mode-volume, vertical-cavity, surface-emitting laser (VCSEL). The VCSEL includes an active structure to emit light upon injection of carriers, and two reflecting structures at least one of which is a grating reflector structure. The active structure is disposed within at least one of the reflecting structures. The reflecting structures are configured as a vertical-cavity resonator of small mode-volume. An optical-bus transmitter including a plurality of small-mode-volume VCSELs, and a system including at least one optical bus and at least one optical-bus transmitter in a digital-information processor, or a data-processing center, are also provided.

Abstract: A solar cell according to the embodiment includes a back electrode layer on a support substrate; a first through hole dividing the back electrode layer into a plurality of back electrodes; a first contact pattern in the back electrode layer; a light absorbing layer formed on the back electrode layer and including a second contact pattern on the first contact pattern; and a front electrode layer on the light absorbing layer.

Abstract: Provided is a light emitting device. In one embodiment, a light emitting device including: a support member; a light emitting structure on the support member, the light emitting structure comprising a first conductive type semiconductor layer, a second conductive type semiconductor layer, and an active layer between the first conductive type semiconductor layer and the second conductive type semiconductor layer; a protective member at a peripheral region of an upper surface of the support member; an electrode including an upper portion being on the first conductive type semiconductor layer, a side portion extended from the upper portion and being on a side surface of the light emitting structure, and an extended portion extended from the side portion and being on the protective member; and an insulation layer between the side surface of the light emitting structure and the electrode.

Abstract: Various embodiments of a 3D high resolution X-ray sensor are described. In one aspect, an indirect X-ray sensor includes a silicon wafer that includes an array of photodiodes thereon with each of the photodiodes having a contact on a front side of the silicon wafer and self-aligned with a respective grid hole of an array of grid holes that are on a back side of the silicon wafer. Each of the grid holes is filled with a scintillator configured to convert beams of X-ray into light. The indirect X-ray sensor also includes one or more silicon dies with an array of photo-sensing circuits each of which including a contact at a top surface of the one or more silicon dies. Contact on each of the photodiodes is aligned and bonded to contact of a respective photo-sensing circuit of the array of photo-sensing circuits of the one or more silicon dies.

Abstract: A method of fabricating a miniaturized semiconductor or other such device takes advantage of a self-reorganization characteristic of an in-situ dissociable diblock copolymer to form a circular via hole that is centrally disposed relative to other device features. In one embodiment, the method is used to form a dual damascene structure. During formation of the dual damascene structure, due to the self-reorganization characteristics of the monomer constituents of the diblock copolymer, the position of the via hole can be ensured to be self aligned with the position of the trench, thus improving the performance and yield of the so formed semiconductor devices, and lowering fabrication costs.

Abstract: To provide a solar cell having improved photoelectric conversion efficiency and a solar cell module. A solar cell (10) is provided with a photoelectric conversion portion (20), a light receiving surface electrode (21a) and a back surface electrode (21b). The light receiving surface electrode (21a) is arranged on the light receiving surface (20a) of the photoelectric conversion portion (20). The back surface electrode (21b) is arranged on the back surface (20b) of the photoelectric conversion portion (20). The back surface electrode (21b) includes metal film (21b1) and an electrical connection electrode (21b2). The metal film (21b1) at least partially covers the back surface (20b). The electrical connection electrode (21b2) is arranged on the metal film (21b1).

Abstract: Prepared is an n? type semiconductor substrate 1 having a first principal surface 1a and a second principal surface 1b opposed to each other, and having a p+ type semiconductor region 3 formed on the first principal surface 1a side. At least a region opposed to the p+ type semiconductor region 3 in the second principal surface 1b of the n? type semiconductor substrate 1 is irradiated with a pulsed laser beam to form an irregular asperity 10. After formation of the irregular asperity 10, an accumulation layer 11 with an impurity concentration higher than that of the n? type semiconductor substrate 1 is formed on the second principal surface 1b side of the n? type semiconductor substrate 1. After formation of the accumulation layer 11, the n? type semiconductor substrate 1 is subjected to a thermal treatment.

Abstract: A three-dimensional display device includes a display panel and a barrier structure. The barrier structure is located at one side of the display panel. Besides, the barrier structure includes a plurality of barrier patterns and a plurality of transparent slits. The barrier patterns and the transparent slits are arranged alternately. In particular, the barrier patterns include a photoelectric conversion structure.

Abstract: Various structures of image sensors are disclosed, as well as methods of forming the image sensors. According to an embodiment, a structure comprises a substrate comprising photo diodes, an oxide layer on the substrate, recesses in the oxide layer and corresponding to the photo diodes, a reflective guide material on a sidewall of each of the recesses, and color filters each being disposed in a respective one of the recesses. The oxide layer and the reflective guide material form a grid among the color filters, and at least a portion of the oxide layer and a portion of the reflective guide material are disposed between neighboring color filters.

Abstract: A light guide portion includes a low refractive index portion and a high refractive index portion. The low refractive index portion has a refractive index equal to or lower than that of an insulating layer. The high refractive index portion has a refractive index higher than that of the low refractive index portion. The low refractive index portion is located above a separating portion, and is sandwiched by the high refractive index portion in a first direction. A width in the first direction of the low refractive index portion at a first position distant from the separating portion in a second direction is narrower than a width in the first direction of the low refractive index portion at a second position closer to the separating portion than the first position in the second direction.

Abstract: The present disclosure relates to a solid-state imaging element and an electronic device capable of suppressing occurrence of a dark current and acquiring higher image quality. The solid-state imaging element includes a high-concentration diffusion layer configured to serve as a connection portion by which a wiring is connected to a semiconductor substrate, and a junction leak control film formed to cover a surface of the diffusion layer. Also, to connect the wiring to the diffusion layer, a width of an opening formed in an insulation film stacked on the semiconductor substrate is greater than a width of the diffusion layer. Further, in a charge accumulation portion configured to accumulate a charge generated by a photoelectric conversion portion generating the charge according to an amount of received light, the junction leak control film is also used as a capacitor film of the charge accumulation portion.

Abstract: A solid-state image pickup device includes an array of a first pixel and a second pixel. The second pixel includes a light shielding portion provided above a photoelectric conversion portion thereof and configured to block some of incident light so as to perform focus detection, and a light guiding portion provided at least above an upper face of the light shielding portion.

Abstract: A photovoltaic device includes a substrate, a transparent conductive oxide, an n-type window layer, a p-type absorber layer and an electron reflector layer. The electron reflector layer may include zinc telluride doped with copper telluride, zinc telluride alloyed with copper telluride, or a bilayer of multiple layers containing zinc, copper, cadmium and tellurium in various compositions. A process for manufacturing a photovoltaic device includes forming a layer over a substrate by at least one of sputtering, evaporation deposition, CVD, chemical bath deposition process, and vapor transport deposition process. The process includes forming an electron reflector layer over a p-type absorber layer.

Abstract: A solid-state imaging device is provided. The solid-state imaging device includes a plurality of arrayed pixels, an optical inner filter layer, and a light-blocking side wall. The plurality of arrayed pixels each includes a photoelectric conversion portion and a pixel transistor. The optical inner filter layer is provided for blocking infrared light and formed facing toward a light-receiving surface of the photoelectric conversion portion of a desired pixel among the arrayed pixels. The light-blocking side wall is formed on a lateral wall of the optical inner filter layer.

Abstract: Resonance enhanced color filter arrays are provided for image sensors. Resonance cavities formed with color filter materials that enhance the color filtering capabilities of the color filter materials. Resonance enhanced color filter arrays may be provided for back side illumination image sensors and front side illumination image sensors. A layer of high refractive index material or metamaterial may be provided between a microlens and a color filter material to serve as a first partially reflecting interface for the resonance cavity. An optional layer of high refractive index material or metamaterial may be provided between color filter material and a substrate. In front side illumination image sensors, color filter material may be provided in a light guide structure that extends through interlayer dielectric. The color filter material in the light guide structure may form at least part of a resonance cavity for a resonance enhanced color filter array.

Abstract: A solar cell includes a substrate of a first conductive type, an emitter region, which is positioned at the substrate and is doped with impurities of a second conductive type opposite the first conductive type, a plurality of first electrodes, which are connected to the emitter region and extend parallel to one another to be spaced apart from one another, a plurality of semiconductor electrodes, which extend in a direction different from an extension direction of the plurality of first electrodes to be spaced apart from one another and have an impurity doping concentration higher than the emitter region, and a second electrode connected to the substrate. A distance between two adjacent semiconductor electrodes is about 0.02 cm to 0.2 cm, and a distance between two adjacent first electrodes is about 0.3 cm to 0.8 cm.

Abstract: To provide a photoelectric conversion device which has little light loss caused by light absorption in a window layer and has favorable electric characteristics. The photoelectric conversion device includes, between a pair of electrodes, a light-transmitting semiconductor layer which has one conductivity type and serves as a window layer, and a silicon semiconductor substrate having a conductivity type for forming a p-n junction or a silicon semiconductor layer having a conductivity type for forming a p-i-n junction. The light-transmitting semiconductor layer can be formed using an inorganic compound containing, as its main component, an oxide of a metal belonging to any of Groups 4 to 8 of the periodic table. The band gap of the metal oxide is greater than or equal to 2 eV.

Abstract: A photocoupler includes: a light emitting element; a light receiving element; and a bonding layer. The light emitting element includes a semiconductor stacked body, and a first and a second electrode. The semiconductor stacked body includes a light emitting layer. The light receiving element includes a first and a second electrode on a side of a light receiving surface. The bonding layer bonds the light emitting element and the light receiving surface, and has transparency and insulating property.

Abstract: An infrared sensor device includes a semiconductor substrate, at least one sensor element that is micromechanically formed in the semiconductor substrate, and at least one calibration element, which is micromechanically formed in the semiconductor substrate, for the sensor element. An absorber material is arranged on the semiconductor substrate in the area of the sensor element and the calibration element. One cavern each is formed in the semiconductor substrate substantially below the sensor element and substantially below the calibration element. The sensor element and the calibration element are thermally and electrically isolated from the rest of the semiconductor substrate by the caverns. The infrared sensor device has high sensitivity, calibration functionality for the sensor element, and a high signal-to-noise ratio.

Abstract: An avalanche photodiode detector is provided. The avalanche photodiode detector comprises an absorber region having an absorption layer for receiving incident photons and generating charged carriers; and a multiplier region having a multiplication layer; wherein the multiplier region is on a mesa structure separate from the absorber region and is coupled to the absorber region by a bridge for transferring charged carriers between the absorber region and multiplier region.

Abstract: A novel germanium (Ge) photodetector is disclosed, containing a stripe layer including Ge, a substrate supporting the stripe layer, and P and N regions, which are located inside the substrate and near opposite sides of the stripe. The stripe layer containing Ge for light absorption is operated in a slow-light mode by adding combinations of a gradual taper indent structure and a periodic indent structure to reduce light scatterings and to control light group velocity inside the stripe. Due to the slower light traveling velocity inside the stripe, the absorption coefficient of the stripe containing Ge is upgraded to be 1 to 2 orders of magnitude larger than that of a traditional bulk Ge at L band, and so the absorption coefficient reaches more than 1 dB/?m at the wavelength of 1600 nm.

Abstract: A solid-state imaging device includes a substrate, a photoelectric conversion section, a first impurity layer having a carrier polarity of a second conductivity type, a charge-to-voltage converting section, an amplifying section, and a second impurity layer having a carrier polarity of the second conductivity type. The second impurity layer is disposed in a region between the photoelectric conversion section and the amplifying section. The second impurity concentration of the second P-type impurity layer is made higher than the first impurity concentration of the first impurity layer.

Abstract: A solid-state image pickup device includes a semiconductor substrate in which photoelectric conversion units are arranged. An insulator is disposed on the semiconductor substrate. The insulator has holes associated with the respective photoelectric conversion units. Members are arranged in the respective holes. A light-shielding member is disposed on the opposite side of one of the members from the semiconductor substrate, such that only the associated photoelectric conversion unit is shielded from light. In the solid-state image pickup device, the holes are simultaneously formed and the members are simultaneously formed.

Abstract: Provided is a semiconductor light receiving device including: a semiconductor substrate; a semiconductor layer laminated on the semiconductor substrate and including an upper surface portion; a reflecting film formed to cover the upper surface portion of the semiconductor layer and including a principal reflecting region and an upper surface; and an upper electrode formed to cover at least one portion of the upper surface of the reflecting film, and including a junction portion extending through the reflecting file to be provided in contact with the upper surface portion of the semiconductor layer, the junction portion of the upper electrode surrounding a portion of a circumference of the principal reflecting region of the reflecting film, the principal reflecting region being connected to a region of the reflecting film located outside the junction portion, in which the semiconductor light receiving device detects light entering from another side of the semiconductor substrate.

Abstract: The photodiode has a p-type doped region (2) and an n-type doped region (3) in a semiconductor body (1), and a pn junction (4) between the p-type doped region and the n-type doped region. The semiconductor body has a cavity (5) such that the pn junction (4) has a distance (d) of at most 30 ?m from the bottom of the cavity (7).

Abstract: A semiconductor apparatus includes: a first sheet-like member having a light receiving surface of an imaging device and a first connection terminal disposed thereon, the imaging device generating an image by receiving incident light from a light collecting section for collecting external light disposed thereon; a second sheet-like member having a second connection terminal to be connected to the first connection terminal provided thereon; a conductive bonding portion made of a conductive material and bonded with the first connection terminal; and a bonding wire connecting the conductive bonding portion and the second connection terminal, wherein the bonding wire is disposed along the plane of the first sheet-like member such that reflected light from the bonding wire does not impinge on the light receiving surface.

Abstract: A photodiode array PDA1 is provided with a substrate S wherein a plurality of photodetecting channels CH have an n-type semiconductor layer 32. The photodiode array PDA1 is provided with a p? type semiconductor layer 33 formed on the n-type semiconductor layer 32, resistors 24 provided for the respective photodetecting channels CH and each having one end portion connected to a signal conducting wire 23, and an n-type separating portion 40 formed between the plurality of photodetecting channels CH. The p? type semiconductor layer 33 forms pn junctions at an interface to the n-type semiconductor layer 32 and has a plurality of multiplication regions AM for avalanche multiplication of carriers generated with incidence of detection target light, corresponding to the respective photodetecting channels. An irregular asperity 10 is formed in a surface of the n-type semiconductor layer 32 and the surface is optically exposed.